DOC: update intersphinx URLs
DOC: update intersphinx URLs

kbarbary/sncosmo,dannygoldstein/sncosmo,dannygoldstein/sncosmo,sncosmo/sncosmo,kbarbary/sncosmo,dannygoldstein/sncosmo,kbarbary/sncosmo,sncosmo/sncosmo,sncosmo/sncosmo